Control to suspend automatic upper ratio shifting

摘要

A partially automated mechanical transmission system (92) having a mechanical transmission (10) with a lower group (first-eighth) of manually shifted ratios and an upper group (ninth-tenth) of ratios with automatic shifting between ratios in the upper group and requiring manual shifting between groups. Control logic is provided to sense a driver intention to retain the transmission engaged in a current engaged upper group ratio until the occurrence of an event, such a manual shift into transmission neutral. In one embodiment, the on/off switch (184) from the cruise control control panel (125) is utilized to provide a signal indicative of operator intent to temporarily suspend automatic upper ratio shifting.